There's the unforgiving sun beating down, the wounds that won't heal, and the impending death on Logan's face. They all take the trendy term "gritty superhero movie" to a new level.

Makeup artist Joel Harlow and his team had the challenging task of taking two very familiar characters — Hugh Jackman's Wolverine and Patrick Stewart's Professor X — and delivering believably aged-up versions of them, while also helping to send them off with dignity.

Heads will roll …

In the first act, Laura (Dafne Keen) cuts off the heads of one of her would-be captors — and throws it to Pierce (Boyd Holbrook).

"We weighted them so they bounced the correct amount. There is the correct weight to those heads because we put lead shot in them, so they didn't bounce like they were made of foam," Harlow tells Heat Vision. "We weighted the jaws. The jaws were independent. No matter the way the head fell, the jaws would go slack with gravity in that direction. That's something I haven't seen done before. As we were making them, I thought, 'This is what's going to sell these heads.' "

Logan's death …

"His look at the end of the film is just really a progression of what he's gone through until then — and certainly in that last battle with X-24 and Pierce, he's sustains a lot of damage," says Harlow. "That was really just a progression of blood splattering on him from the X-24 … Open wounds, gunshots. All of that."

Harlow actually worked for one week on 2000's X-Men, helping create some of the sandy footprints for Senator Kelly (Bruce Davison). Since then he's been a fan of the franchise as a viewer.

"To come in as this new guy and kill off two very important characters, the cornerstones of the franchise, it was a tremendous responsibility and it was something we didn't take lightly," he says. "Certainly the last day that Hugh worked, I got a picture with him. Same with Patrick on his last day."

Embracing the violence …

Harlow hadn't worked on a film that was rated R for violence in years, and faced an adjustment period of how gruesome to go. It wasn't until spending a day filming the first fight of the production — Laura vs. the Reavers in the smelting plant — that he decided to rethink everything.

"I said, 'OK you know what? We're going to resculpt all these wounds,' " he recalls. "We're going to just push the envelope because that's the movie we're making."

Embracing the violence included the film's most disturbing scene, in which an innocent family, the Munsons, (including their teenage son Nate, played by Quincy Fouse) is killed by the X-24.

"It is tragic. And you don't want to undersell that with a couple of scrapes. As makeup department head, it needed to be that graphic. It needed to be that intense so that you'd really feel for these characters. There's no room in this film to shortchange any of that," says Harlow.

The most-wanted nonagenarian in the world …

"Patrick and I had had conversations before we got to set … just about discoloring the fingernails, discoloring age spots, liver spots, rogue hairs that grow out of the ears and out of the eyebrows," says Harlow. "And it's that kind of subtle work if it wasn't there, you probably wouldn't miss it, but it's subtle enough that it doesn't draw attention to it. It's just another texture in these characters."

Crafting Caliban …

The character was muted, but things get complicated as the film goes on and he's been beaten and subjected to sunlight, which burns his skin.

"When we see him in the morgue sequence in the gymnasium and he's completely burnt. That was a full-body burn," says Harlow. "You don't see it in the film, but it was the longest makeup for Stephen {Merchant] on the film, 3.5 hours to get him into that. I wanted his clothes to look like they had fused to his skin, everything burned together. I had seen reference pictures and it touched a nerve."